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प्रश्न
What is the magnification of the images formed by plane mirrors and why?
The magnification produced by a plane mirror is +1. What does this mean?
उत्तर
As m = `(h_2)/(h_1) = +1`
h2 = h1
i.e., the size of the image is equal to the size of the object. Further, the + sign of m indicates that the image is erect and hence virtual..
संबंधित प्रश्न
The height of the image formed by an object of height 10 cm placed in front of a plane mirror is __________.
(a) 5 cm
(b) 10 cm
(c) 15 cm
(d) 20 cm
Where should an object be placed in front of the concave mirror so as to obtain its virtual, erect and magnified image?
Which one of these circumstances enables a concave mirror to be used as a shaving mirror?
The image formed by a concave mirror is real, inverted and of the same size as the object. The position of the object must then be:
(a) at the focus
(b) between the centre of curvature and focus
(c) at the centre of curvature
(d) beyond the centre of curvature
What sign (+ve or −ve) has been given to the following on the basis of Cartesian Sigh Convention?
Height of a real image.
What is the nature of image formed by a concave mirror if the magnification produced by the mirror
+4
What is the nature of image formed by a concave mirror if the magnification produced by the mirror
−2?
Fill in the following blank with suitable word:
If the magnification has a plus sign, than image is ......... and.........
When an object is placed at a distance of 36 cm from a convex lens, an image of the same size as the object is formed. What will be the nature of image formed when the object is placed at a distance of:
10 cm from the lens?
A convex lens produces a magnification of + 5. The object is placed:
(a) at focus
(b) between f and 2f
(c) at less than f
(d) beyond 2f
In order to obtain a magnification of, –0.75 with a convex lens of focal length 8 cm, the object should be placed:
(a) at less than 8 cm
(b) between 8 cm and 16 cm
(c) beyond 16 cm
(d) at 16 cma
A magnifying lens has a focal length of 100 mm. An object whose size is 16 mm is placed at some distance from the lens so that an image is formed at a distance of 25 cm in front of the lens.
What is the distance between the object and the lens?
A magnifying lens has a focal length of 100 mm. An object whose size is 16 mm is placed at some distance from the lens so that an image is formed at a distance of 25 cm in front of the lens.
Where should the object be placed if the image is to form at infinity?
An image formed on a screen is three times the size of the object. The object and screen are 80 cm apart when the image is sharply focussed.
Calculate focal length of the lens.
For a plane mirror, magnification m = ______.
Assertion: The focal length of the mirror is /and the distance of the object from the focus is V then the magnification of the mirror will be `("f"/"f−u")`
Reason: Magnification = `"image distance"/ "object distance"` = `(-"v"/"u")`
What is the nature of the image formed by a concave mirror if the magnification produced by the mirror is +4?
The power of a lens is +4D. Find the focal length of this lens. An object is placed at a distance of 50 cm from the optical centre of this lens. State the nature and magnification of the image formed by the lens and also draw a ray diagram to justify your answer.
